I. Field of the Invention
This invention relates to a package comprising a liquid chemical or chemical dissolved or dispersed in a liquid or gel which is contained in an envelope of water soluble or water dispersible material.
II. Discussion of the Prior Art
At present, most hazardous liquids are stored in metal drums or, where smaller quantities are required, plastic containers.
Hazardous compounds, especially agrochemical compounds, are formulated in a variety of ways. It is, however, especially desirable for farmers to handle such compounds when they are in liquid form. This facilitates the spreading of such compounds. There are, however, difficulties and drawbacks in handling liquids. The liquids can be spilled on the ground or may leak due to holes in the containers. The containers may also rupture when subjected to a physical shock.
It is thus difficult to devise a containerization system that is suitable for farmers, safe for those handling the containers and also safe for the environment.
It is known that agrochemicals may be contained in soluble bags or sachets made from film. However, such films may crack and break and thus cause spillage of the agrochemicals they contain. In fact, a variety of defects may be present in films, which lead to weaknesses of the film and consequently a potential source of leakage. The presence of air bubbles, dust particles or other foreign bodies, of gel particles or of thin points on or in the film are all potential weak points. If a film with such a weak point is subjected to a lot of handling or physical shock, the film may fail at that point. This is especially a problem in the agrochemical industry where containers may be subjected to rough or unsafe handling by distributors or farmers.
The weaknesses of films mentioned above are present to a greater or lesser extent in certain types of films, depending on their method of manufacture. When films are made by casting, there may be fewer pinholes, but there are more often tiny pieces of gel inclusions. When films are made by extrusion, there are more pinholes.